When its raining or snowing, it obstructs your view in cockpit mode (thats what the windshield wipers are for!), but not in the other views. I think that the reduced visibility is a distinct part of the challenge of driving in interesting weather, and switching to an outside-the-car viewpoint takes away that challenge, akin to using a driving aid.
(And takes a lot of the fun out of flying down the Mulsanne Straight, at night, in heavy rain, near-zero traction, surrounded by clouds of spray that hide the exact locations of nearby cars, watching desperately through the rain-spattered windshield so you dont miss the chicane distance signs (your only landmarks in this rainy mess), and clinging to the steering wheel for dear life! 
)
So, in an online race, it
could be considered a point of fairness that everyone uses cockpit view (or
no one does) when its raining/snowing. Perhaps thats part of the point OP was making? Some option there to force cockpit view? (Or, some way to reduce visibility in
all camera modes, for those who dont like cockpit view in general.)
(I skimmed over the thread, and I dont think anyone brought this up. So
I will!)
However, as a general thing, I dont like the idea of forcing one persons personal preference on others. I prefer cockpit view, myself, and I wouldnt want to be
forced to use, say, chase view, just because the room host swears by it. That should work the other way around too.
